@Sathish M, a couple of things here that will help ensure you get assistance in this user forum.

Be sure to limit your post to a single question. The reason for this is that once a discussion starts w/ the initial question it no longer appears as 'unanswered' and this is something others look for when trying to help.

alway use "Reply" rather than "Answer" button if you are replying to someone. "Answer" button is intended to be used for when you want to offer an answer to the person asking the question.

Many questions are already answered in the Community and I encourage you to use the search bar at the top of the Community forum. Just type in a few key words and hit enter and you will be presented w/ a number of threads that might answer your question. If not then you should feel free to post a new question. While you can skip this step and simply post a question you may get your answer more quickly searching first.

With that said, I believe that @Johan_Soetens__Cleverty_ has presented you with good sources for creating the email channel that will allow your customer to submit tickets via email. If you are still having issues w/ that (your original question) please "reply" to original Answer that offered the links. Your other questions are unclear but I would direct you to the third bullet above as a means of resolution.